1. Field of the Invention
This invention is related to a magnetic transmission structure and in particular to one wherein the driven member will be rotated with the driving member without direct interconnecting members.
2. Description of the Prior Art
The laser module of the conventional laser level is generally driven by means of a belt or gears, or directly driven by a motor. However, the driving shaft of the motor is eccentric with the center line of the laser module when they are drivingly connected by a belt or gears, i.e. the shaft of the motor cannot be arranged in alignment with the center line of the laser module, thereby resulting in vibration to the laser module and therefore influencing the accuracy of the laser beam. In addition, the motor must be mounted at one side of the laser level and cannot be installed at the center of the laser level, so that the stability of the laser level will be influenced when the motor is turning. Hence, it is proposed to connect the laser module directly with the output shaft of the motor, so that the motor can be mounted at the center of the laser level so as to increase the stability thereof Nevertheless, the output shaft of the motor is easily engaged with the bearing once the laser level is subjected to vibration and furthermore, the vibration of the motor will be transmitted to the laser module thereby influencing the accuracy thereof.
Furthermore, carbon brushes of the motor will be worn out in a short period of time at high speed so that it is necessary to replace the carbon brushes regularly in order to keep the conductivity. However, the laser module must be re-adjusted in position whenever the carbon brushes are replaced thereby causing much inconvenience in use.
Therefore, it is an object of the present invention to provide a magnetic transmission structure which can obviate and mitigate the above-mentioned drawbacks.
This invention is related to a magnetic transmission structure for laser levels.
It is the primary object of the present invention to provide a magnetic transmission structure for laser levels wherein the driven member can be rotated with the driving member without direct interconnecting members.
It is another object of the present invention to provide a magnetic transmission structure for laser levels which can provide accurate measurements.
It is a further object of the present invention to provide a magnetic transmission structure for laser levels which is durable in use.
According to a preferred embodiment of the present invention, a magnetic transmission structure for a laser level includes a driving member provided with two opposite first chambers in each of which is fitted a magnet, a driven member provided with two opposite second chambers arranged in alignment with the first opposite chambers, each of the second chamber being provided with a magnet, and a motor having an output axle drivingly connected with an intermediate portion of the driving member.